Up until 10 days ago, my bath/shower combination had cold water coming out of the spout. I have a single lever on/off switch, and in the cold water position there is almost no pressure, and no cold water- the water is luke warm. The fixtures and plumbing are about 20 years old. My husband did some work on the toilet in the same bathroom recently, could that have done anything to the water pressure in the tub? Thank you.

Marienl- One thing you can do first is to check to see in behind tub shower unit to see if you have a bad water leak or can hear water running, if you don't see or hear anything and you are on city water go out to the water meter and watch it for a few minuts to see if the needle is moveing, most of newer meters have a small red needle also, it's more less a small leak detecter ,the smallest leak will show up more quick there, If you have no luck here, you need to call a plumber ;;;; The single handle is compicated to work on. Since your husband just worked on cold water line ,there could be some trash in water line and got into faucet.If I have helped answer your question rate my answer below .F.B.E.